Method and apparatus for securing metal mounting elements on a glass surface

ABSTRACT

A method of securing metal fasteners to the surface of a glass object, particularly a spectacle lens, which comprises the steps of applying against said surface, with a predetermined and adjustable pressure, a fastener made of a metal adapted to be easily welded to the glass object and consisting of a piece of extruded section shaped as consistent with the manner in which the fastener is to be accomadating subsequently, the glassengaging base of said fastener accompdating the contour of said glass surface, and the step of vibrating each fastener at a supersonic frequency during a few seconds.

United States Patent Delmas 1 Apr. 25, 1972 [54] METHOD AND APPARATUSFOR SECURING METAL MOUNTING ELEMENTS ON A GLASS SURFACE [72] Inventor:Jean-Raymond Delmas, Vanves, France [73] Assignee: Societe DesLunetiers, Paris, France [22] Filed: May 12, 1969 [21] App]. No.:823,814

52 U.S.C1 ..29/472.9,228/1,29/20, 156/73, 29/473.1, 29/4975 s1 lm.Cl..B23k31/02 [58] Field of Search ..228/1; 29/20, 472.9, 473, .1,

[56] References Cited UNITED STATES PATENTS 3,203,715 8/1965 Benbenek..29/472.9 3,257,721 6/1966 Jones ..228/1 3,372,851 3/1968 Wands.........228/1 3,414,963 12/1968 Cheng..... ....29/472.9 3,447,236 6/1969Hatcher ..29/472.9

3,461,542 8/1969 Schoenthaler ..29/472.9 3,523,357 8/1970 Meyer..29/472.9

FOREIGN PATENTS OR APPLICATIONS 964,391 l/l950 France ..29/473.l1,244,868 9/1960 France ..29/472.9

Primary ExaminerJohn F. Campbell Assistant Examiner-Donald P. RooneyAttorney-Holman & Stern [5 7] ABSTRACT 5 Claims, 7 Drawing Figu'esBACKGROUND OF THE INVENTION The present invention is concerned with amethod of securing metal mounting elements or fasteners to the surfaceof a glass object, and also with an apparatus for carrying out saidmethod.

The possibility of securing metal mounting elements or fasteners to thesurface of a glass article or object is extremely useful andadvantageous in many cases, were it only for facilitating:

the positioning by suspension of a glass plate in a metalcoating vesselor like bell-shaped enclosure, A

the fitting of optical lenses in a lens mount or in an eyepiece, and

the fitting of ophthalmic lenses on a spectacle mounting.

In this last case; mountings pertaining to the three main typesmentioned hereinafter have been widely used:

1. The rim mounting requiring the preliminary grinding of the lens edgein order to form either a double bevel thereon, in case the lens is tobe fitted in a metal or plastic frame or rim, or a groove if the lens isto be retained in its mounting by using a simple wire, usually a Nylonwire. It is known that the first alternative is considered as ratherobsolete, and that the second one is objectionable in that it isdelicate to carry out and/or most likely to give a fragile article,especially if the lens edge is relatively thin.

2. The glued mounting performed by using a rapidly' polymerizable resinis extremely simple but the end product is also fragile. 3. The screwmounting, requiring the preliminary drilling of the glass, is certainlyreliable but the drilling operation is always attended by the risk ofbreaking the lens.

SUMMARY OF THE INVENTION Now it is the essential object of the presentinvention to provide a method of securing metal fasteners to a glasssurface which combines the advantageous features of these conventionalmounting methods but is nevertheless free of their inconveniences; inother words, the method of this invention is applicable withoutpractically any risk of breaking the glass while providing an extremelyreliable and strong glass-tometal assembly.

To this end, the method of the present invention comprises the followingsteps:

a. Applying to a surface of a glass object, under a predeterminedadjustable pressure, fasteners made from a metal easily weldable toglass and which consist each of a piece of section having in crosssection a shape consistent with the type of mounting to be fitted tosaid fasteners and having a base accommodating the contour of said glasssurface;

b. vibrating said fasteners, preferably in succession, at a supersonicfrequency, each during a few seconds.

Provided that the two adjacent glass and metal surfaces are properlyapplied against each other, a very satisfactory and reliablemetal-to-glass weld is thus obtained, due to the local expansion ofthese two materials which assists their mutual molecular penetration.

Advantageously, said fasteners consist of aluminum and are sections cutfrom an extruded material having its cross-sectional contour designed asa function of the manner in which the fasteners are secured to theglass, on the one hand, and on the mounting on the other hand, with thesupersonic frequency utilized being preferably of the order of 40,000Hz.

It is another object of this invention to provide an apparatus forcarrying out the method disclosed hereinabove, which is designedparticularly for properly positioning and subsequently locking in theselected positions on the one hand the glass object before the weldingstep, and on the other hand the fasteners. The general arrangement ofthis apparatus is derived directly from the steps constituting themethod of this invention, with its structure being designed in eachspecific case as a function of the manner in which the fasteners are tobe secured to the glass and to the mounting, therefore of the shape ofthese fasteners,

BRIEF DESCRIPTION OF THE DRAWINGS.

The invention will be better understood from the following descriptionof a typical form of embodiment of the apparatus for carrying out themethod described hereinabove, this description being made with referenceto the accompanying drawings in which:

FIG. 1 is a front elevational view showing a spectacle lens secured to amounting by means of two fasteners welded to the lens according to themethod of this invention;

FIG. 2 is a diagrammatic front elevational view showing a typical formof embodiment of the apparatus of this invention for welding fastenersof the type shown in FIG. 1;

FIGS. 3 and 4 are fragmentary detail views, respectively in frontelevation and in vertical section, showing the vibrating pin of theapparatus of FIG. 2, with a fastener ready to be fitted on said pin;

FIG. 5 is a part-sectional view showing only the lens-support of theapparatus of FIG. 2, the section being taken along the line VV of FIG.2;

FIGS. 6 and 7 are diagrammatic views, respectively in front elevationand in side elevation, showing another type of fastener and anothermanner of securing the same to a spectacle lens and to the spectaclemounting.

DESCRIPTION OF THE PREFERRED EMBODIMENT.

Referring firstly to FIG. 1, it will be seen that an ophthalmic lens 1is provided with two metal fasteners 2,, 2 welded to the upper edge ofthe lens and adapted to be secured by means of screws to a front bar 3of a spectacle mounting.

Referring now to FIG. 2, it will be seen that an apparatus according tothis invention comprises essentially two identical vibrating assemblies10, and 10 disposed symmetrically in relation to a lens supportingdevice 30. Each vibrating assembly, for example assembly 10,, carries anadjustable vibrating rod or Sonotrode of known type, having acylindrical end 11, and an intermediate portion 12, of revolution withan exponential meridian. The dimensions of the end II and portion 12, ofthis rod are calculated to obtain a resonance frequency of the assemblyof the order of 40,000 Hz. I

The excitation of this rod 11,, 12 is obtained by energizing amagnetostrictive vibrator 13, known per se and connected to anadjustable frequency generator (not shown) of electrical oscillations,also known per se.

The assembly 10, is pivotally mounted about a horizontal pin 141. Thispin carried by a bracket 15, is rigid with a circular metal collar 16,adapted to clamp the section 12, of the assembly by means of three setscrews (not shown) disposed at spaced intervals, therefore at thevertices of an equilateral triangle. The same collar 16, carries on theother hand an arm 17, bent twice on itself so that the outermost portionof this arm be substantially parallel to the geometric axis of rod1l,-12,. A counterweight 181 is adapted to slide along this outermostportion of arm 17, to an adjustment position in which it is adapted tobe locked by means of a set screw 19,,

9 a PUEPBSJZEO be siafsss tlxt The rod 11,, 12, carries near its freeend a cylindrical pin 20, secured to the rod end through any suitablemeans (not shown), so as to extend substantially at right angles to saidrod. As shown in FIGS. 3 and 4, the pin 20, has on the one hand abevelled end, i.e. a pair of convergent or oblique flat faces 21,disposed symmetrically in relation to a diametral plane of said pin, andon the other hand a longitudinal median slot 22,.

On this pin 20, an aluminium fastener 2 is adapted to be fitted orengaged in smooth frictional contact, with this fastener consisting inthe example illustrated of a short piece of inverted-T metal section.The web of the T is adapted to engage the slot 22,. The fastener 2, alsocomprises a pair of lateral flanges 2,, adapted on the one hand toreinforce the T- shaped section and on the other hand to improve thefitting of the fastener 2, on said pin 20,. Finally, the web of the Thas a central through hole 2,, to permit the insertion of a screw forsecuring the fastener 2 to the mounting 3 (see FIG. 1.)

Referring now to FIGS. 2 and 5, it will be seen that the lens support 30comprises a metal base 31 adjustable and adapted to be locked in theselected position by means of a wing screw 32. Another screw is providedfor adjustably securing to this base 31 a frame 33 of plastic or othersuitable material, of which thecontour or edge of a hollow portioncorresponds in shape to the contour of the opthalmic lens 1 in order toprevent any movement of this lens in its plane (i.e. parallel to theplane ofFIG. 2).

The lens support 30 comprises on the other hand an upstanding bracket 34having a strap-shaped upper portion between the arms of which isadjustably mounted a lens-holding block 36 pivoted by means of atransverse shaft 35 and adapted to be locked in the selected position bymeans of a pair of knurled knobs 37. The lens 1 can be held against thefront face of block 36, for example, by the action of pneumatic' vacuumproduced either by a vacuum pump (not shown) or by a suction-cup (notshown). Thus, the ophthalmic lens 1 can be inclined by an angle a sothat the upper edge of the lens (see FIG. 5) is substantially horizontaland the fasteners 2,, 2 fitted on the pins 20,, 20,, of vibratingassemblies 10,, respectively can be applied with a pressure adjustableby means of the counterweights 18,, 18 against said upper edge.

This apparatus is utilized as follows:

.The fasteners 2,, 2 are fitted on the pins 20,, 20 and the position oflens 1 is properly adjusted. The fasteners 2,, 2 are then pressedagainst the top edge of lens 1 by means of the counterweights 18,, 18Then the assembly 10, is vibrated during a few seconds, and subsequentlythe other assembly 10 is also vibrated during a few seconds. Thus, thetwo welds are obtained almost simultaneously.

The vibrations of rods 11,, 12 and 11 12 under resonance conditions canbe adjusted by observing the screen of an oscillograph (not shown)incorporated in the oscillation generator, with this adjustment beingsubsequently preserved by using a self-monitoring system of known type(not shown), all these means being well known per se.

In the above description it is assumed that the fasteners are secured tothe top edge of a spectacle lens and adapted to be secured in turn bymeans of screws to the spectacle mounting. However, this specificarrangement should not be construed as limiting the field of theinvention since it would also be possible for example, and as shown inFIGS. 6 and 7, to use a fastener in the form of a cylindrical wire 4,possibly sectioned as required by the curvature of the lens 1, to weldor fuse this fastener not to the top edge of the lens 1 but simply on asmall flat surface thereof, so that the thus equipped lens can subsequently fit'by snap action into the mounting 3. In this case, ofcourse, the apparatus described hereinabove with reference to FIGS. 2 to5 would be modified accordingly, as will readily occur to anybodyconversant with the art.

I claim:

1. A method of securing metal fasteners to the surface of a glassspectacle lens, which comprises the step of applying against saidsurface, with a predetermined and adjustable pressure, at least onefastener made of a metal adapted to be easily welded to the glassmaterial of the lens and consisting of a piece of extruded sectionshaped as consistent with the manner in which the fastener is to be usedsubsequently, each fastener having a glass-engaging base accommodatingthe contour of said glass lens surface, and being applied against saidsurface of the lens in a predetermined orientation also consistent withthe manner in which the fastener is to be used subsequently, and thestep of vibrating each fastener at a supersonic frequency during a fewseconds while maintaining constant said predetermined orientation.

2. The method as set forth mclaim 1, wherein, upon a plur'ality offasteners being secured to a same glass surface, said fasteners arevibrated separately and successively. q

3. The method as set forth in claim 1, wherein said at least onefastener is vibrated at a supersonic frequency of the order of 40,000Hz.

4. A method of securing metal fasteners to the surface of a glassobject, particularly a spectacle lens, which comprises applying againstsaid surface, with a predetermined and adjustable pressure, at least onefastener made of a metal adapted to be easily welded to the glass objectand consisting of a relatively short piece of T-section having a smallhole formed through the central web of the T- to permit a subsequentinsertion of a retaining screw therethrough, the glass-engaging base ofthe fastener accommodating the contour of said glass surface, andvibrating said at least one fastener at a supersonic frequency during afew seconds while maintaining constant said predetermined orientation.

5. A method of securing metal fastenersto the surface of a glass object,particularly a spectacle lens, which comprises applying against saidsurface, with a predetermined and adjustable pressure, at least onefastener of a material adapted to be easily welded to the glass objectand consisting of a section of cylindrical wire to permit a subsequentsnap-fitting of the glass

1. A method of securing metal fasteners to the surface of a glass spectacle lens, which comprises the step of applying against said surface, with a predetermined and adjustable pressure, at least one fastener made of a metal adapted to be easily welded to the glass material of the lens and consisting of a piece of extruded section shaped as consistent with the manner in which the fastener is to be used subsequently, each fastener having a glass-engaging base accommodating the contour of said glass lens surface, and being applied against said surface of the lens in a predetermined orientation also consistent with the manner in which the fastener is to be used subsequently, and the step of vibrating each fastener at a supersonic frequency during a few seconds while maintaining constant said predetermined orientation.
 2. The method as set forth in claim 1, wherein, upon a plurality of fasteners being secured to a same glass surface, said fasteners are vibrated separately and successively.
 3. The method as set forth in claim 1, wherein said at least one fastener is vibrated at a supersonic frequency of the order of 40,000 Hz.
 4. A method of securing metal fasteners to the surface of a glass object, particularly a spectacle lens, which comprises applying against said surface, with a predetermined and adjustable pressure, at least one fastener made of a metal adapted to be easily welded to the glass object and consisting of a relatively short piece of T-section having a small hole formed through the central web of the T- to permit a subsequent insertion of a retaining screw therethrough, the glass-engaging base of the fastener accommodating the contour of said glass surface, and vibrating said at least one fastener at a supersonic frequency during a few seconds while maintaining constant said predetermined orientation.
 5. A method of securing metal fasteners to the surface of a glass object, particularly a spectacle lens, which comprises applying against said surface, with a predetermined and adjustable pressure, at least one fastener of a material adapted to be easily welded to the glass object and consisting of a section of cylindrical wire to permit a subsequent snap-fitting of the glass and fastener assembly in a mounting, the glass-engaging base of the fastener accommodating the contour of said glass surface, and vibrating said at least one fastener at a supersonic frequency during a few seconds while maintaining constant said predetermined orientation. 